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Mammoths: Resurrecting Extinct Megafauna

Larry D. Agenbroad (edited for middle school readability by KMcg)

An ActionBioscience.org original article


April 2005

The Woolly Mammoth at the Royal BC Museum, Victoria, British Columbia. Source: Wikimedia Commons.

Approximately 11,000 years ago 76 percent of North American megafauna (those animals weighing more than 100 pounds) became extinct, though the causes of the extinction are still unknown. Perhaps the most readily recognizable member of that group is the mammoth.

Mammoths are extinct relatives of elephants.

Mammoths are members of the family Elephantidae. Their closest living relatives are the African elephants (Loxodonta africana and Loxodonta cyclotis) and the Asian elephant (Elephas maximus). Elephantidae appeared in North Africa nearly 3.5 million years ago and migrated to Europe, Asia, and ultimately to North America.

Woolly mammoths have been preserved in permafrost frozen soil.

There were several species of mammoths in North America: pygmy forms (Mammuthus exilis) inhabiting islands off the coast of California; large, temperate grassland forms (Mammuthus columbi); and sub-Arctic denizens (Mammuthus primigenius), known as woolly mammoths. Woolly mammoths have been preserved in the permafrost zones of the Arctic regions—especially Siberia and Alaska—presenting the possibility of creating a living reproduction of an extinct animal through cloning.

The cloning question


Cloning an extinct mammoth is a possibility.

The recovery of the Jarkov Mammoth from the permafrost of the Taimyr Peninsula, Siberia, was featured in the Discovery Channel’s television documentary “Raising the Mammoth.” A portion of the program was devoted to the possibility of cloning a woolly mammoth, if high-quality DNA could be recovered from the carcass. That concept caught the imagination of people of all ages worldwide. The response was a large number of questions and comments, both pro and con, on the possibility, feasibility (possibility), and consequences of such an endeavor or trial.

To date no mammoth DNA has been suitable for cloning.

The DNA recovered from the Jarkov Mammoth was of insufficient quantity and quality to allow any further experiments with that individual. Another mammoth, known as the Fishhook Mammoth , also from the Taimyr Peninsula, provided better DNA but was still unsuitable for a cloning process. Many researchers feel there will never be a good enough DNA sample preserved in animals frozen under natural conditions because of the degrading effects of freeze-thaw cycles and microbes in the soil. On the other hand, there are many frozen specimens within the permafrost regions of the northern hemisphere, and one of them may produce satisfactory DNA.1,2

Cloning mammoths is controversial.

The controversy


Almost instantaneously, opposition to a possible cloning project began. The arguments fell into several categories: (1) legality of cloning, (2) morality, (3) feasibility, and (4) potential of success. These will be addressed briefly here.

There are no legal barriers to cloning mammoths.



Legality

One of the first items to surface on the Internet was a legal brief from the Stanford University Law School, San Jose, California.3 This treatise covers many aspects of potentially cloning a mammoth, but it basically concludes there is no legal barrier, nationally or internationally, to prevent such an experiment.

Some protests are based on religious and ethical arguments.

Morality

The question of the morality of such a project was addressed in the legal brief mentioned above, but it was encountered most commonly in emails, letters, articles, and verbal exchanges. These reactions fell into several general groupings (and miscellaneous others):

(a) These animals are extinct. Are we playing God by trying to resurrect them?

(b) Cloning will create monsters that will destroy life as we know it.

(c) There are no modern environments suitable for these creatures.

(d) It would be inhumane.

(e) Such an endeavor would release a plague of unknown diseases on Earth.

The counterpoints to these arguments are as follows:

Humans had a role in killing off mammoths.

A mammoth clone would be reared by an elephant mother.

(a) Mammoths are extinct, yet some remnant or part of populations survived to at least 3700 years ago on a small island in the Arctic Ocean.4 There is also evidence that mammoths were on St. Paul Island, in the Alaskan Pribolofs, until as late as 7980 years ago.5 How did two populations of insular mammoths survive the extinction of continental mammoths? There is compelling evidence that humans had a role in mammoth extinction, at least in North America. If humans were instrumental in mammoth extinction, perhaps human technology would compensate, or make up for it, by allowing them to once again walk the Earth.

(b) If such a project, however conceived, were successful, the result would not be some monster out of Jurassic Park. It would be similar to an elephant, although hairier. Initially, it would look and act like a juvenile elephant, needing to be nurtured, guided, and taught by the surrogate elephant mother that carried it in the womb.

Environmental conditions for mammoths can be recreated.

Mammoth clones would not be laboratory specimens.

There is no evidence of transmissible disease from defrosted specimens.

(c) Many people, including some of the Siberian expedition team, claim it would be impossible to replicate the environment of the woolly mammoth, and therefore cloning would be a disservice to the restored mammoth. We do not actually know what the environmental conditions were where the woolly mammoth lived; in fact, finding out is one of the research goals of restoring the extinct animal. Most experts agree that the woolly mammoth lived in a cold, dry grassland called the Mammoth Steppe.6 Many of the plants found in the digestive tract of the frozen mammoths still grow in Siberia today. Even if there is no remnant of the mammoth’s environment, we have expert nutritionists on hand who could create “mammoth chow” (in very large bags, of course). In Sahka (or Yakutia) land has been set aside for a Pleistocene Park where muskoxen, bison, and Przewalski’s horses have been reintroduced alongside the native animals such as bears, wolves, and reindeer. The only missing megafauna are woolly mammoths, woolly rhinos, and cave lions. Russian scientists have stated they would welcome clones to the park.

(d) We have been besieged by people who say, “it is not humane to clone a mammoth,” “it will be treated just like a laboratory rat,” “why don’t you use the research expertise for projects that benefit humans, like the recent cloning of five piglets to supply heart valves?” But is it humane to clone creatures that will be butchered for their body parts, to be used as spares for humans?

(e) As for loosing plagues on the Earth, there are hundreds of frozen, extinct animals that are defrosted by natural means each year. To our knowledge there have been no recorded maladies or plagues from such natural events.



Feasibility

Experts in the cloning field have claimed that if DNA of suitable quality and quantity is recovered, there will be little difficulty in producing a clone. The cloning potential lies in two differing methodologies:

There are two avenues to cloning a mammoth.

(1) Sex cells. A Japanese team of researchers headed by Drs. K. Goto and A. Iritani has attempted several expeditions to collect sex cells (eggs or sperm) from frozen mammoths in Siberia. To date, these attempts have failed. (Note: Even if successful, this method would produce a hybrid offspring, 50 percent Mammuthus and 50 percent Elephas.)

(2) Body cells. As with Dolly, the cloned sheep, it is not necessary to have sexual reproduction to obtain a clone. In this technique, the egg of an Asian elephant would have the nucleus destroyed and replaced with the nucleus of a mammoth specimen. If successful, the resulting clone would be genetically all mammoth.

Possibilities of success
The technology of cloning is new and its potential mostly unrealized, but there are reasons to be optimistic:

Animals have already been cloned successfully.



  • There have been many recent cloning successes: sheep, calves, kittens, monkeys, guars, mouflon sheep, the Arabian oryx, the African quagga, and others.

  • Successful cloning of an extinct species may lead to techniques and procedures to save currently endangered species. Examples include the Japanese ibis, the Chinese giant panda, the Australian hairy nosed wombat, and others.

  • There may even be successes with recently extinct animals such as the New Zealand moa and the Tasmanian thylacine, or marsupial wolf.

  • There is also the possibility of creating a frozen zoo for sperm, eggs, and cells of endangered species.

I’ll conclude with a statement by Salsberg: “With these procedural and ethical standards and safeguards in place, it is my belief that the benefits of resurrecting the mammoth can be fully realized, while minimizing or completely avoiding most, if not all, of the project’s harms and questionable applications.”3

A different perspective


Modern animals exterminated by humans are being reintroduced to native areas.

There are parallels between reintroducing modern and extinct species.

A very different perspective, at least from the view of a North American, is shown by the following analogy: It can be demonstrated that humans had a hand in the North American extinction of the mammoths (and possibly other Pleistocene megafauna). There are numerous mammoth kill sites as evidence (although too few in the view of Grayson and Meltzer,7,8 who were rebutted by Fiedel and Haynes9).

Leaving that argument to stand, consider the following: In prehistoric and protohistoric North America there were many wolves (Canis lupis) and grizzly bears (Ursus horribilis). With the expansion of European settlers as farmers and ranchers, these carnivores were exterminated, or at least removed from large regions of western North America, often with the aid of national governments. Now, in the late 20th and early 21st centuries, wolves and grizzly bears are being reintroduced to former ranges, in spite of the opposition of farmers and ranchers, with the support and protection of national governments.



Conclusion: If two carnivores were exterminated from areas of western North America by humans and are now being reintroduced to old ranges, is there a moral, legal, ethical, or environmental difference from the proposed reintroduction (albeit by cloning) of an extinct herbivore (mammoth), which can be demonstrated to have been driven to extinction (at least in part) by humans?


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